|  |  | Summary

Now that you completed this chapter, you should have a firm understanding of the following: Network-layer routing functions include network addressing and best path selection for traffic. Routing tables store information on possible destinations and how to reach each of the destinations. Routed protocols are protocols that are routed over a network, and routing protocols are protocols that maintain routing tables between routers. Routing protocols can be either static or dynamic. Interior protocols are used for routing networks that are under a common network administration, and exterior protocols are used to exchange routing information between networks that do not share a common administration. IGRP is a distance-vector interior gateway protocol and uses a combination of user-configurable metrics including network delay, bandwidth, reliability, and load. The stability of IGRP is improved by using holddowns, split horizons and poison reverse updates. To configure IGRP, the only mandatory task is to create the IGRP routing process. Other tasks are optional.
| Threaded Case Study
Washington School District Project Task: Routing Protocols and Configuring IGRP

In this chapter, you have learned concepts and configuration processes that will help you implement IGRP as the routing protocol in the Washington School District network. As part of the IGRP configuration and implementation, you need to complete the following tasks:

1. Identify and gather the information required to implement IGRP at the schools' networks and across the district network. Add the information you gather to the existing user requirements and LAN design.
2. Identify and document the networks that will be advertised by the routers in the school district and add that information to the requirements and LAN design. Study and report on the effects of a dynamic routing protocol such as IGRP on the overall performance and maintenance of the entire school district network.
3. Identify and document the IGRP AS number for the school district.
4. Document the router command sequence needed to implement IGRP on the school's router and document the changes in the router configuration.
5. Describe the process that the routers go through to ensure that the neighbor routers are aware of the status of all networks in the AS. This will include the frequency with which routing table updates are sent and the effects of the updates on bandwidth utilization.
6. Identify the best settings for maximum hops, hold-down timer, update timer, and so on. Also, document appropriate bandwidth settings for serial interfaces.
7. Continue LAN Design Tasks: Site Wiring Designs, LAN Logical Designs, Typical MDF and IDF Designs and Electronics Tables, and a Site-specific LAN Electronics List
8. Apply the CCNA Certification Exam Learning Objectives to your specific design. This will require a paragraph on how the learning objectives relate to your design. Learning objectives can be grouped together for the purpose of explanation. In this way, you will be studying for their CCNA Certification Exam as you work through the case study.

CCNA Certification Exam Learning Objectives (*** are explicit CCNA Exam objectives; unmarked are knowledge assumed by the exam):

OSI model

- Describe the three major portions of an IP address.
- Describe the functions of the TCP/IP network-layer protocols and how they are used for path determination.

Routing Protocols:

- Add the IGRP routing protocol to your configuration.***
- Describe the function of a router in delivering data packets between different networks
- Describe the function and limitations of static route entries in a Router.
- Describe the functions and advantages of dynamic routing protocols.
- Describe the difference between routed and routing protocols.
- Describe the function of a routing table in the router.
- Describe what a routing metrics is and what the various components mean.
- Describe the difference between distance vector and link state routing protocols.
- Describe what convergence is in a network.
- Describe what an autonomous network is and what general type of protocol is used to communicate between autonomous networks

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